The present invention relates to III-nitride heterojunction type devices and methods for fabrication thereof.
Known III Nitride heterojunction devices include the heterojunction of two III-nitride semiconductor bodies having different band gaps and/or lattice constants that includes a carrier rich region referred as a two dimensional electron gas or 2-DEG which permits conduction between a source electrode and a drain electrode. Typically, a gate electrode is disposed between the source and the drain electrodes which is operable to interrupt or restore the 2-DEG in order to switch the current from an ON state to an OFF state and vice versa. III-nitride devices have a conduction resistance R and a charge QSW measured between the source and drain electrodes.
It is very desirable in many applications to minimize the product of R and QSW.
Moreover, typical III-nitride devices are depletion mode devices.
It is desirable to obtain an enhancement mode III-nitride power device in order to reduce the amount of power necessary for the operation thereof, among other reasons.